Research under this grant has proceeded in several directions: A. C-glycyronidation. We have now established that delta 6-THC under certain conditions is converted in mouse liver into a C-glycyronide which is a very unusual type of metabolite. B. Interaction of cannabionoids with model membranes. Delta 1-Tetrahydrocannabinol and cannabidiol at high concentrations caused fusion of liposome vesiles which we employ as model membranes; at low concentrations delta 1-THC increased the mobility of the hydrocarbon chains of lecithine in vesicles containing cholesterol while cannabidiol had the opposite effect. C. Comparison of cannabidiol with other anticonvulsive drugs. Both in the crystal state and as free molecules cannabidiol and diphenyl hydantoin have a close conformational relationship. D. Structure-activity relationships. Synthetic studies are underway to help determine the stereochemical requirements for cannabinoid activity.